Residents of this military town tried to go about their work and errands as usual, but their feelings turned to quiet concern as word spread that hundreds of their Marine Corps neighbors had landed for combat in Afghanistan.

Members of the 26th Marine Expeditionary Unit based at Camp Lejeune were among about 1,000 Marines who seized an airfield near the Taliban stronghold of Kandahar as they began the first wave of a ground campaign designed to root out Usama bin Laden and his terrorist network.

The Marines went into combat for the first time late Monday, sending helicopter gunships aloft as Navy fighter jets attacked an armored convoy near the seized air base.

"It's definitely different than before, but — sad as it sounds — life must go on," said Laura McFarland, 22, a gas station employee in Jacksonville whose brother is in the Navy and boyfriend is a Marine.

Along the thoroughfare leading to Camp Lejeune, flags fly from telephone poles at intersections, billboards and business signs carry patriotic slogans and symbols, and cars bear red, white and blue ribbons on antennas and Marine Corps stickers in back windows.

Germaine Quinones, shopping with his 2-year-old daughter on Monday, said his neighbors are aware of the troops' presence in Afghanistan but aren't upset because the U.S.-supported forces appear to be winning.

"If things were kind of hot over there, I'd probably have another opinion," Quinones said. "I think maybe it's because things seem to be in control there, the government that needs to be replaced is losing the battle."

The arrival of the Marines marked a new level of engagement in the campaign in Afghanistan, which had been dominated by bombing runs against Taliban and Al Qaeda targets.

Defense Secretary Donald Rumsfeld suggested that the newly landed Marines, who also include the members of the 15th Marine Expeditionary Unit from Camp Pendleton, Calif., would be tightening the squeeze on Taliban leaders and bin Laden's Al Qaeda network.

"They started this fight, and you are going to finish it," Lt. Col. Christopher Bourne, 41, of Camp Pendleton told his troops Sunday night before boarding a helicopter aboard the San Diego-based USS Peleliu, the lead ship of the attack force.

There are more than 4,000 Marines in the two units contributing troops to the operation, most of them on ships in the Arabian Sea.

President Bush said the Marines — trained to handle a variety of missions including mountain warfare, special operations, peacekeeping and counterterrorism — would assist in hunting down terrorists linked to the Sept. 11 attacks against the United States.

But he cautioned on Monday that as the war enters a new phase, "America must be prepared for loss of life."

There was no official word on casualties after the Marines went into combat near the seized air base Monday night.

"As far as our thoughts here at Camp Pendleton, Marines always train at a high state of readiness. It's our job to always be ready," said Lt. Mamie Ward, 26, of Crystal City, Mo., a spokeswoman for the base.

First Lt. Dan McSweeney, who was part of the 24th Marine Expeditionary Unit that was replaced by Camp Lejeune's 26th Marine Expeditionary Unit, echoed her sentiment.

"Basically, when we did the turnover ... people were aware that Marines may be called upon in a variety of missions," McSweeney said.

Residents in military towns like Jacksonville are accustomed to military deployments and maneuvers, said Lance Cpl. Michael Randolph. "They've all dealt with military life in some way, so it's to be expected," he said.

At "Saigon Sam's" military surplus store across from Camp Geiger — a training base next to Lejeune — co-owner Kandey Butler said she had spoken with military personnel who dropped by about the deployment.

"They're not concerned," she said. "For this to be a military town, they don't worry themselves about it."